Perry County Emergency Management Director Charles Colwell said the workers were working on the well, which produces both oil and natural gas, when the explosion occurred Wednesday around 2:15 p.m. EDT.
State police said Bill Chandler, 36, of Lost Creek, died at the scene of the explosion. State police initially said Chandler was missing, but was later found at the site of the explosion.
Patrick Jeffers, 29, of Winfield, Tenn., was flown to the University of Kentucky Medical Center in Lexington. The Fayette County Coroner said Jeffers died at about 5:30 p.m. EDT,
A third man, William Douglas Bell, 37, of Helenwood, Tenn., was flown to Cincinnati University Hospital. State police said Bell was in critical condition Wednesday night.
Flames were still reaching above the treetops Wednesday evening on a hillside where the well was located. Dozens of people gathered in the parking lot of the Bulan post office to watch black smoke churning into the air.
Colwell said about 25 homes and businesses were evacuated because six crude-oil tanks, each in excess of 10,000 gallons, were at risk of catching fire.
``We heard a boom. It kind of shook the house,'' said Ralph Stanfill, who lives near the fire.
Shortly afterward, Stanfill was evacuated and was still waiting Wednesday evening for an opportunity to head back home.
Mark York, spokesman for the Kentucky Cabinet for Environmental and Public Protection, said a crew from Journey Operating LLC, which owns the well, was servicing the well when the explosion occurred. The Houston-based company has a Leslie County office in Wooten and others throughout eastern Kentucky.
The state's environmental response team is on the scene, as well as state inspectors who were investigating the cause of the explosion. A crew from Boots & Coots Inc. of Houston, a well extinguishing company, arrived at the well around 8:30 p.m. EDT and were working on putting out the fire, state police said.
Kentucky State Police Trooper Scott Hopkins said no one knows what might have happened. The workers were pulling tubing out of the well and replacing a pump, he said.
``It's just too early to make any determination,'' Hopkins said.
Kentucky 476 and Kentucky 550 were closed to traffic and were expected to remain closed for at least 24 hours.
An emergency shelter was set up at a gymnasium in Hazard for the evacuated families.
He said local residents will not be able to return home until after the well is capped.
